In a motor, a rotor having a permanent magnet, which faces pole teeth of stator yokes, is rotated by switching a direction of electric current passing through coils of stator units. The coils are electrically connected to a motor circuit board for controlling the current direction, etc. For example, in an ordinary brushless motor, a magnet wire is wound on a stator iron core in a direction parallel to an axial direction of the stator iron core (a winding direction is perpendicular to the axial direction), and a start end and a terminal end of the coils are extracted in the axial direction and connected to a drive circuit.
In a stator unit of an inner rotor type PM stepping motor, a magnet wire is wound on coil bobbins, which are provided on outer circumferences of pole teeth of stator yokes, and an inner end and an outer end of the magnet wire are extracted to a space outside of the stator, through a winding section of a motor case, and connected to a circuit board (see Patent Document 1).
In another inner rotor type PM stepping motor, large-sized bobbins are used without employing a circuit board, base ends of terminal pins are fixed to the bobbins, a start end and a terminal end of a magnet wire are respectively connected to the terminal pins, and the terminal pins are extended in an axial direction and directly connected to a circuit board at front ends (see Patent Document 2).
In an outer rotor type PM stepping motor, a plurality of bobbins, in each of which through-holes are formed in a flange section and on each of which a coil is formed, are stacked, on core sections of the bobbins, in a state where the through-holes are corresponded to each other, terminal rods are fitted in the through-holes and coil leads, which are extracted into grooves of the outer flange section, are respectively connected to the terminal rods so as to supply electric power (see Patent Document 3).